Program cac_tam_giac;
Uses Crt;
Var a,b,c, s: real;
Begin
Assign(input,'tamgiac.inp');reset(input);
Assign(output,'tamgiac.out');rewrite(output);
Write('Nhap cac so a, b, c: '); readln(a, b, c);
If (a<=0) or (b<=0) or (c<=0) then
Writeln('Khong co tam giac thoa man')
Else
Begin
If ((a+b)<=c) or ((b+c)<=a) or ((a+c)<=b) then
Writeln('a,b,c khong phai la ba canh cua tam giac.')
Else
Begin
Writeln('a,b,c la ba canh cua tam giac.');
{kiem tra tam giac deu}
If (a=b) and (a=c) then
Writeln('Do la tam giac deu.')
else
{kiem tra tam giac vuong}
If (a*a=b*b+c*c) or (b*b=a*a+c*c) or (c*c =a*a+b*b) then
Writeln('Do la ba canh cua tam giac.')
else
{kiem tra tam giac can}
If (a=b) or (b=c) or (c=a) then Writeln('Do la tam giac can:')
else
{kiem tra cac truong hop con lai tam giac thuong}
Writeln('Do la tam giac thuong:');
End;
End;
Readln;
End.